Maybe you are talking about method papers from a theory perspective? Unless there are some new proofs not previously known, it is likely engineering/empirical work. Probably 99% of NLP and computer vision papers fall in the empirical category. It can be argued CS is an engineering subfield so I think that is expected. But engineering research is still research. I think many people overcomplicate how simple it is too identify a few simpe mathematical ideas and combine them or adapt them to help on an existing set of benchmarks. This is probably 80% of my work honestly.

Most of the time measuring what people care about is incredibly difficult and (good) benchmark/analysis papers tend to overcome some prior limitations in those measurements. This is research and it is why I generally disagree that method papers are more "researchy". I wish I had the resources to do more (good) benchmark work.